Figure 2.

PCR amplification of the Cry1Ac gene. M, DL marker 2,000; CK⁻, negative control (non-transgenic poplar); CK⁺, positive control (plasmid pBtiA); the others are the 6-year-old transgenic lines. 19 transgenic lines and the positive control were all detected the expected bands (749 bp), while the negative control was not detected.